1. Field of the Invention
The present invention relates to an expansion unit for an electronic device, in particular, to an expansion unit rotatably connected to the electronic device.
2. Description of Related Art
For the convenience of carrying, the volumes of the electronic products are continuously reduced, and consequently some functions are removed. In order to restore or expand the functions of the electronic products, expansion accessories are commonly selected. When the expansion accessories are used, the expansion accessories are connected to the electronic products, and when not, the expansion accessories are detached therefrom. Therefore, the expansion accessories may achieve a higher flexibility of the electronic products in use.
Currently, a mobile internet device (MID) emphasizing the capability of accessing the internet anywhere has been put forward in the market. Since the MID stresses on the function of wirelessly accessing the internet anywhere, under the requirements for limited volume and size of the image display, the press button keyboard, commonly seen on a notebook computer, is not employed in the MID, and the display occupies a main operation surface of the MID instead.